Fearfully and Wonderfully Made

Your Wonderful Skin

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Skin—the largest organ of the body

Barrier against pathogens

Waterproof

The epidermis contains Langerhans cells

Secretes antibacterial substances

Tough and durable

Weighs about 8–10 pounds and area is about 22 square feet

Is rejuvenated about every 4 weeks3

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Protects against heat and cold

Stores water, fat, and vitamins, and can absorb some soluble substances

Protects underlying tissues from ultraviolet radiation

Internal mechanisms regulate cell division, DNA repair, etc., to promote healing in injured skin

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Regulation—Body temperature, synthesis in vitamin D, flow of blood, salt levels, evaporation

Contains an extensive network of nerve cells—sensors for heat, cold, touch, pain.

Has an ecosystem for all the bacteria on its surface. Microorganisms keep each other in check on healthy skin.

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But this strong protective layer can be overcome by a mosquito, and

yellow fever, zika, malaria, and other diseases result.

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